Currently, trench capacitors within an integrated circuit are made by filling the previously formed trench with appropriately doped polycrystalline silicon. A common method for depositing the polycrystalline silicon is by chemical vapor deposition techniques. The heavily doped polysilicon provides one of the conductive plates for the trench capacitor. A significant disadvantage associated with this present method is that the polysilicon has a relatively high electrical resistivity as compared to elemental metals. This high electrical resistivity accordingly limits the speed of the resulting device. In addition, the current deposition processes which are utilized to refill the trench with the polysilicon are extremely time consuming and expensive.
Therefore, it would be desirable to provide a trench capacitor within an integrated circuit, wherein the trench capacitor is metal-filled and accordingly characterized by relatively low electrical resistivity. It would be further desirable to provide a method for forming the trench capacitor which is not unduly time consuming or expensive.